1
general::
Phrase(s): take the lid off (of) something [and] take the lid off
1. Lit. to remove the lid from something. (Of is usually retained before pronouns.) • I took the lid off the box and set it aside. • Karen took off the lid. 2. Fig. to reveal a set of previously concealed problems. (Of is usually retained before pronouns.) • You took the lid off this mess. You straighten it out! • You took off the lid, so you have to settle it.
McGrawhill's American Idioms And Phrasal Verbs